1OWTAP(1) One-Wire File System OWTAP(1)
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6 owtap - Packet sniffer for the owserver protocol
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9 owtap -p owtap-tcp-port -s owserver-tcp-port
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12 1-Wire
13 1-wire is a wiring protocol and series of devices designed and manufac‐
14 tured by Dallas Semiconductor, Inc. The bus is a low-power low-speed
15 low-connector scheme where the data line can also provide power.
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17 Each device is uniquely and unalterably numbered during manufacture.
18 There are a wide variety of devices, including memory, sensors (humid‐
19 ity, temperature, voltage, contact, current), switches, timers and data
20 loggers. More complex devices (like thermocouple sensors) can be built
21 with these basic devices. There are also 1-wire devices that have
22 encryption included.
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24 The 1-wire scheme uses a single bus master and multiple slaves on the
25 same wire. The bus master initiates all communication. The slaves can
26 be individually discovered and addressed using their unique ID.
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28 Bus masters come in a variety of configurations including serial, par‐
29 allel, i2c, network or USB adapters.
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31 OWFS design
32 OWFS is a suite of programs that designed to make the 1-wire bus and
33 its devices easily accessible. The underlying principle is to create a
34 virtual filesystem, with the unique ID being the directory, and the
35 individual properties of the device are represented as simple files
36 that can be read and written.
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38 Details of the individual slave or master design are hidden behind a
39 consistent interface. The goal is to provide an easy set of tools for a
40 software designer to create monitoring or control applications. There
41 are some performance enhancements in the implementation, including data
42 caching, parallel access to bus masters, and aggregation of device com‐
43 munication. Still the fundamental goal has been ease of use, flexibil‐
44 ity and correctness rather than speed.
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46 owserver
47 owserver (1) is the backend component of the OWFS 1-wire bus control
48 system. owserver (1) arbitrates access to the bus from multiple client
49 processes. The physical bus is usually connected to a serial or USB
50 port, and other processes connect to owserver (1) over network sockets
51 (tcp port).
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53 Frontend clients include a filesystem representation: owfs (1) , and a
54 webserver: owhttpd (1). Direct language bindings are also available,
55 e.g: owperl (3).
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57 There are also many light-weight clients that can only talk to owserver
58 [1m(1) and not to the 1-Wire bus directly. They include shell and multiple
59 language modules (perl, Visual Basic, python,...)
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61 owserver protocol
62 All the owserver (1) clients use the owserver protocol for communica‐
63 tion. The owserver protocol is a well documented tcp/ip client/server
64 protocol. Assigned the "well known port" default of 4304.
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66 owtap
67 owtap (1) is interposed between owserver (1) and clients, to display
68 and help resolve communication problems. Network communication is for‐
69 warded in both directions, but a visual display is also created, with
70 statistics and "drill-down" of individual packets.
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73 -p
74 TCP port or IPaddress:port for owtap
75 Other OWFS programs will access owtap via this address. (e.g. owdir -s
76 IP:port /)
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78 -s
79 TCP port or IPaddress:port for owserver
80 The tcp port (IP:port) for the "upstream" owserver.
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83 If owserver (1) is started:
84 owserver -p 4304 -d /dev/ttyS0
85 owserver on tcp port 4304 and connects to a physical 1-wire bus on a
86 serial port.
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88 You can directly query owserver (1) with
89 owdir -s 4304 /
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91 To see the protocol in action:
92 owtap -s 4304 -p 3000
93 owdir -p 3000 /
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95 In this case owtap (1) is connecting to owserver (1) on the original
96 port (4304) and offering a new port (3000) for clients.
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99 owtap (1) is a pure Tcl/TK program and will run wherever Tcl/TK is
100 available (Windows, Macintosh, Linux, Unix)
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103 owserver protocol
104 http://www.owfs.org/index.php?page=owserver-protocol
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106 Tcl/TK
107 http://www.tcl.tk
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110 Programs
111 owfs (1) owhttpd (1) owftpd (1) owserver (1) owdir (1) owread (1)
112 owwrite (1) owpresent (1) owtap (1)
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114 Configuration and testing
115 owfs (5) owtap (1) owmon (1)
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117 Language bindings
118 owtcl (3) owperl (3) owcapi (3)
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120 Clocks
121 DS1427 (3) DS1904(3) DS1994 (3) DS2404 (3) DS2404S (3) DS2415 (3)
122 DS2417 (3)
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124 ID
125 DS2401 (3) DS2411 (3) DS1990A (3)
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127 Memory
128 DS1982 (3) DS1985 (3) DS1986 (3) DS1991 (3) DS1992 (3) DS1993 (3)
129 DS1995 (3) DS1996 (3) DS2430A (3) DS2431 (3) DS2433 (3) DS2502 (3)
130 DS2506 (3) DS28E04 (3) DS28EC20 (3)
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132 Switches
133 DS2405 (3) DS2406 (3) DS2408 (3) DS2409 (3) DS2413 (3) DS28EA00 (3)
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135 Temperature
136 DS1822 (3) DS1825 (3) DS1820 (3) DS18B20 (3) DS18S20 (3) DS1920 (3)
137 DS1921 (3) DS1821 (3) DS28EA00 (3) DS28E04 (3)
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139 Humidity
140 DS1922 (3)
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142 Voltage
143 DS2450 (3)
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145 Resistance
146 DS2890 (3)
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148 Multifunction (current, voltage, temperature)
149 DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3) DS2756 (3)
150 DS2760 (3) DS2770 (3) DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)
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152 Counter
153 DS2423 (3)
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155 LCD Screen
156 LCD (3) DS2408 (3)
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158 Crypto
159 DS1977 (3)
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161 Pressure
162 DS2406 (3) -- TAI8570
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165 http://www.owfs.org
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168 Paul Alfille (paul.alfille@gmail.com)
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172OWTAP Manpage 2007 OWTAP(1)